Fatigue Modeling and Numerical Analysis of Re-Filling Probe Hole of Friction Stir Spot Welded Joints in Aluminum Alloys

In the present study, the fatigue behavior and tensile strength of A6061-T4 aluminum alloy, joined by friction stir spot welding (FSSW), are numerically investigated. The 3D finite element model (FEM) is used to analyze the FSSW joint by means of Abaqus software. The tensile strength is determined for FSSW joints with both a probe hole and a refilled probe hole. In order to calculate the fatigue life of FSSW joints, the hysteresis loop is first determined, and then the plastic strain amplitude is calculated. Finally, by using the Coffin-Manson equation, fatigue life is predicted. The results were verified against available experimental data from other literature, and a good agreement was observed between the FEM results and experimental data. The results showed that the joint’s tensile strength without a probe hole (refilled hole) is higher than the joint with a probe hole. Therefore, re-filling the probe hole is an effective method for structures jointed by FSSW subjected to a static load. The fatigue strength of the joint with a re-filled probe hole was nearly the same as the structure with a probe hole at low applied loads. Additionally, at a high applied load, the fatigue strength of joints with a refilled probe hole was slightly lower than the joint with a probe hole.

[1]  L. Manuel,et al.  Residual stress effects on fatigue life prediction using hardness measurements for butt-welded joints made of high strength steels , 2021 .

[2]  R. Hedayati,et al.  Fatigue Life Improvement of Cracked Aluminum 6061-T6 Plates Repaired by Composite Patches , 2021, Materials.

[3]  S. Schmauder,et al.  Increasing Fatigue Life of 09Mn2Si Steel by Helical Rolling: Theoretical–Experimental Study on Governing Role of Grain Boundaries , 2020, Materials.

[4]  F. Berto,et al.  Fatigue assessment of high strength welded joints through the strain energy density method , 2020 .

[5]  F. Berto,et al.  Fatigue properties of AA6060‐T6 butt welds made by hybrid metal extrusion & bonding , 2020 .

[6]  M. M. Mashhadi,et al.  Numerical analysis of cracked aluminum plate repaired with multi-scale reinforcement composite patches , 2020 .

[7]  R. Ulewicz,et al.  Profile and Areal Surface Parameters for Fatigue Fracture Characterisation , 2020, Materials.

[8]  W. Bochnowski,et al.  Fatigue Life Assessment of Refill Friction Stir Spot Welded Alclad 7075-T6 Aluminium Alloy Joints , 2020 .

[9]  R. Branco,et al.  Cyclic plastic behaviour of 7075 aluminium alloy , 2020 .

[10]  E. Crăciun,et al.  Effect of Thermomechanical Loading on an Edge Crack of Finite Length in an Infinite Orthotropic Strip , 2019, Mechanics of Composite Materials.

[11]  M. Givi,et al.  Effects of Vibration on Microstructure and Thermal Properties of Friction Stir Spot Welded (FSSW) Aluminum Alloy (Al5083) , 2019, International Journal of Precision Engineering and Manufacturing.

[12]  Yang Yu,et al.  Interface Behavior and Impact Properties of Dissimilar Al/Steel Keyhole-Free FSSW Joints , 2019, Metals.

[13]  K. Faes,et al.  Weldability of high-strength aluminium alloy EN AW-7475-T761 sheets for aerospace applications, using refill friction stir spot welding , 2019, Welding in the World.

[14]  Jidong Kang,et al.  Microstructure and Fracture Behavior of Refill Friction Stir Spot Welded Joints of AA2024 Using a Novel Refill Technique , 2019, Metals.

[15]  A. Gerlich,et al.  Microstructure, static and fatigue properties of refill friction stir spot welded 7075-T6 aluminium alloy using a modified tool , 2019, Science and Technology of Welding and Joining.

[16]  A. Mostafapour,et al.  Finite element and experimental investigation on the effects of temperature, strain and strain rate on microstructure and mechanical properties of FSSWed TRIP steel joints , 2018, Materials Research Express.

[17]  H. Akebono,et al.  Effect of welding time on fatigue properties of friction stir spot welds of Al to carbon fibre-reinforced plastic , 2018, Science and Technology of Welding and Joining.

[18]  A. Y. Khenyab,et al.  Effect of Underground Corrosion on the Buckling of Al Alloy 6061-T4 Columns under Increasing Load , 2018, Al-Nahrain Journal for Engineering Sciences.

[19]  S. I. Jaffery,et al.  Numerical and experimental investigation of Johnson–Cook material models for aluminum (Al 6061-T6) alloy using orthogonal machining approach , 2018, Advances in Mechanical Engineering.

[20]  S. Kashani-Bozorg,et al.  Microstructure and property assessment of dissimilar joints of 6061-T6 Al/dual-phase steel fabricated by friction stir spot welding , 2018, Welding in the World.

[21]  F. Berto,et al.  Low-Cycle Fatigue Behavior of 10CrNi3MoV High Strength Steel and Its Undermatched Welds , 2018, Materials.

[22]  N. Arzola,et al.  Weld Magnification Factor Approach in Cruciform Joints Considering Post Welding Cooling Medium and Weld Size , 2018, Materials.

[23]  F. Berto,et al.  Fatigue life assessment of notched round bars under multiaxial loading based on the total strain energy density approach , 2017, Theoretical and Applied Fracture Mechanics.

[24]  H. Svoboda,et al.  Tool geometry optimization in friction stir spot welding of Al-steel joints , 2017 .

[25]  W. Li,et al.  Friction Stir Spot Welding: A Review on Joint Macro- and Microstructure, Property, and Process Modelling , 2014 .

[26]  M. Mohammadpour,et al.  A novel method for improving fatigue life of friction stir spot welded joints using localized plasticity , 2014 .

[27]  Soran Hassanifard,et al.  Weld arrangement effects on the fatigue behavior of multi friction stir spot welded joints , 2013 .

[28]  A. Abood,et al.  Effect of Heat Treatment on Strain Life of Aluminum Alloy AA 6061 , 2013 .

[29]  Toshihiro Shimizu,et al.  Fatigue behaviour of dissimilar friction stir spot welds between A6061-T6 and low carbon steel sheets welded by a scroll grooved tool without probe , 2011 .

[30]  X. Li,et al.  Effect of tool geometry on hook formation and static strength of friction stir spot welded aluminum 5754-O sheets , 2009 .

[31]  Keiro Tokaji,et al.  Effect of re-filling probe hole on tensile failure and fatigue behaviour of friction stir spot welded joints in Al–Mg–Si alloy , 2008 .

[32]  Keiro Tokaji,et al.  Effect of tool geometry on microstructure and static strength in friction stir spot welded aluminium alloys , 2007 .

[33]  Ali Fatemi,et al.  Application of bi-linear log–log S–N model to strain-controlled fatigue data of aluminum alloys and its effect on life predictions , 2005 .

[34]  Jwo Pan,et al.  Microstructures and Failure Mechanisms of Spot Friction Welds in Lap-Shear Specimens of Aluminum 6111-T4 Sheets , 2004 .